[PATCH 1/2] powerpc: split the math emulation into two parts

[Kumar Gala]

On Jul 16, 2013, at 6:57 AM, Kevin Hao wrote:

> For some SoC (such as the FSL BookE) even though there does have
> a hardware FPU, but not all floating point instructions are
> implemented. Unfortunately some versions of gcc do use these
> unimplemented instructions. Then we have to enable the math emulation
> to workaround this issue. It seems a little redundant to have the
> support to emulate all the floating point instructions in this case.
> So split the math emulation into two parts. One is for the SoC which
> doesn't have FPU at all and the other for the SoC which does have the
> hardware FPU and only need some special floating point instructions to
> be emulated.
> 
> Signed-off-by: Kevin Hao <haokexin at gmail.com>
> ---
> arch/powerpc/Kconfig           | 20 ++++++++++++++++++++
> arch/powerpc/math-emu/Makefile | 24 ++++++++++++------------
> arch/powerpc/math-emu/math.c   | 20 ++++++++++++++------
> 3 files changed, 46 insertions(+), 18 deletions(-)

why make the split, what harm is there in just turning on the full emulation code to handle the unimplemented cases?

who says what some other implementation doesn't need something that you have in CONFIG_MATH_EMULATION_FULL?

Is the kernel code size really an issue?

- k